LabVIEW brain computer interface for EEG analysis during sleep stages

In this paper is proposed a brain-computer interface. In order to develop and implement this interface, the programming environment LabVIEW was used. In order to recognize a K complex in the EEG signal, a simple detector was created, using Peak Detector VI in LabVIEW. The detector receives the representation of the power spectrum of the signal and determines the locations and the amplitudes of signals above a certain limit (the limit can be set by moving the horizontal bar in the power spectrum). Then the code determines if the peak correspond to those which designate a K complex. Following these experimental achievements where an EEG signal was used, it was determined that one could reliably observe a K complex in the data from the sleep spindles, focusing on only 2 peaks in the power spectrum. The first peak should appear between 0,5 and 1.50 Hz, having an amplitude exceeding 65 units, while the second peak should appear between 5 and 10 Hz, having an amplitude of at least 30 units.